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path: root/src/gallium/drivers/radeonsi/si_buffer.c
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/*
 * Copyright 2013 Advanced Micro Devices, Inc.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * on the rights to use, copy, modify, merge, publish, distribute, sub
 * license, and/or sell copies of the Software, and to permit persons to whom
 * the Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHOR(S) AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 * USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#include "radeonsi/si_pipe.h"
#include "util/u_memory.h"
#include "util/u_upload_mgr.h"
#include "util/u_transfer.h"
#include <inttypes.h>
#include <stdio.h>

bool si_rings_is_buffer_referenced(struct si_context *sctx,
				   struct pb_buffer *buf,
				   enum radeon_bo_usage usage)
{
	if (sctx->ws->cs_is_buffer_referenced(sctx->gfx_cs, buf, usage)) {
		return true;
	}
	if (radeon_emitted(sctx->dma_cs, 0) &&
	    sctx->ws->cs_is_buffer_referenced(sctx->dma_cs, buf, usage)) {
		return true;
	}
	return false;
}

void *si_buffer_map_sync_with_rings(struct si_context *sctx,
				    struct si_resource *resource,
				    unsigned usage)
{
	enum radeon_bo_usage rusage = RADEON_USAGE_READWRITE;
	bool busy = false;

	assert(!(resource->flags & RADEON_FLAG_SPARSE));

	if (usage & PIPE_TRANSFER_UNSYNCHRONIZED) {
		return sctx->ws->buffer_map(resource->buf, NULL, usage);
	}

	if (!(usage & PIPE_TRANSFER_WRITE)) {
		/* have to wait for the last write */
		rusage = RADEON_USAGE_WRITE;
	}

	if (radeon_emitted(sctx->gfx_cs, sctx->initial_gfx_cs_size) &&
	    sctx->ws->cs_is_buffer_referenced(sctx->gfx_cs,
						resource->buf, rusage)) {
		if (usage & PIPE_TRANSFER_DONTBLOCK) {
			si_flush_gfx_cs(sctx, RADEON_FLUSH_ASYNC_START_NEXT_GFX_IB_NOW, NULL);
			return NULL;
		} else {
			si_flush_gfx_cs(sctx, RADEON_FLUSH_ASYNC_START_NEXT_GFX_IB_NOW, NULL);
			busy = true;
		}
	}
	if (radeon_emitted(sctx->dma_cs, 0) &&
	    sctx->ws->cs_is_buffer_referenced(sctx->dma_cs,
						resource->buf, rusage)) {
		if (usage & PIPE_TRANSFER_DONTBLOCK) {
			si_flush_dma_cs(sctx, PIPE_FLUSH_ASYNC, NULL);
			return NULL;
		} else {
			si_flush_dma_cs(sctx, 0, NULL);
			busy = true;
		}
	}

	if (busy || !sctx->ws->buffer_wait(resource->buf, 0, rusage)) {
		if (usage & PIPE_TRANSFER_DONTBLOCK) {
			return NULL;
		} else {
			/* We will be wait for the GPU. Wait for any offloaded
			 * CS flush to complete to avoid busy-waiting in the winsys. */
			sctx->ws->cs_sync_flush(sctx->gfx_cs);
			if (sctx->dma_cs)
				sctx->ws->cs_sync_flush(sctx->dma_cs);
		}
	}

	/* Setting the CS to NULL will prevent doing checks we have done already. */
	return sctx->ws->buffer_map(resource->buf, NULL, usage);
}

void si_init_resource_fields(struct si_screen *sscreen,
			     struct si_resource *res,
			     uint64_t size, unsigned alignment)
{
	struct si_texture *tex = (struct si_texture*)res;

	res->bo_size = size;
	res->bo_alignment = alignment;
	res->flags = 0;
	res->texture_handle_allocated = false;
	res->image_handle_allocated = false;

	switch (res->b.b.usage) {
	case PIPE_USAGE_STREAM:
		res->flags = RADEON_FLAG_GTT_WC;
		/* fall through */
	case PIPE_USAGE_STAGING:
		/* Transfers are likely to occur more often with these
		 * resources. */
		res->domains = RADEON_DOMAIN_GTT;
		break;
	case PIPE_USAGE_DYNAMIC:
		/* Older kernels didn't always flush the HDP cache before
		 * CS execution
		 */
		if (!sscreen->info.kernel_flushes_hdp_before_ib) {
			res->domains = RADEON_DOMAIN_GTT;
			res->flags |= RADEON_FLAG_GTT_WC;
			break;
		}
		/* fall through */
	case PIPE_USAGE_DEFAULT:
	case PIPE_USAGE_IMMUTABLE:
	default:
		/* Not listing GTT here improves performance in some
		 * apps. */
		res->domains = RADEON_DOMAIN_VRAM;
		res->flags |= RADEON_FLAG_GTT_WC;
		break;
	}

	if (res->b.b.target == PIPE_BUFFER &&
	    res->b.b.flags & PIPE_RESOURCE_FLAG_MAP_PERSISTENT) {
		/* Use GTT for all persistent mappings with older
		 * kernels, because they didn't always flush the HDP
		 * cache before CS execution.
		 *
		 * Write-combined CPU mappings are fine, the kernel
		 * ensures all CPU writes finish before the GPU
		 * executes a command stream.
		 *
		 * radeon doesn't have good BO move throttling, so put all
		 * persistent buffers into GTT to prevent VRAM CPU page faults.
		 */
		if (!sscreen->info.kernel_flushes_hdp_before_ib ||
		    sscreen->info.drm_major == 2)
			res->domains = RADEON_DOMAIN_GTT;
	}

	/* Tiled textures are unmappable. Always put them in VRAM. */
	if ((res->b.b.target != PIPE_BUFFER && !tex->surface.is_linear) ||
	    res->b.b.flags & SI_RESOURCE_FLAG_UNMAPPABLE) {
		res->domains = RADEON_DOMAIN_VRAM;
		res->flags |= RADEON_FLAG_NO_CPU_ACCESS |
			 RADEON_FLAG_GTT_WC;
	}

	/* Displayable and shareable surfaces are not suballocated. */
	if (res->b.b.bind & (PIPE_BIND_SHARED | PIPE_BIND_SCANOUT))
		res->flags |= RADEON_FLAG_NO_SUBALLOC; /* shareable */
	else
		res->flags |= RADEON_FLAG_NO_INTERPROCESS_SHARING;

	if (sscreen->debug_flags & DBG(NO_WC))
		res->flags &= ~RADEON_FLAG_GTT_WC;

	if (res->b.b.flags & SI_RESOURCE_FLAG_READ_ONLY)
		res->flags |= RADEON_FLAG_READ_ONLY;

	if (res->b.b.flags & SI_RESOURCE_FLAG_32BIT)
		res->flags |= RADEON_FLAG_32BIT;

	/* Set expected VRAM and GART usage for the buffer. */
	res->vram_usage = 0;
	res->gart_usage = 0;
	res->max_forced_staging_uploads = 0;
	res->b.max_forced_staging_uploads = 0;

	if (res->domains & RADEON_DOMAIN_VRAM) {
		res->vram_usage = size;

		res->max_forced_staging_uploads =
		res->b.max_forced_staging_uploads =
			sscreen->info.has_dedicated_vram &&
			size >= sscreen->info.vram_vis_size / 4 ? 1 : 0;
	} else if (res->domains & RADEON_DOMAIN_GTT) {
		res->gart_usage = size;
	}
}

bool si_alloc_resource(struct si_screen *sscreen,
		       struct si_resource *res)
{
	struct pb_buffer *old_buf, *new_buf;

	/* Allocate a new resource. */
	new_buf = sscreen->ws->buffer_create(sscreen->ws, res->bo_size,
					     res->bo_alignment,
					     res->domains, res->flags);
	if (!new_buf) {
		return false;
	}

	/* Replace the pointer such that if res->buf wasn't NULL, it won't be
	 * NULL. This should prevent crashes with multiple contexts using
	 * the same buffer where one of the contexts invalidates it while
	 * the others are using it. */
	old_buf = res->buf;
	res->buf = new_buf; /* should be atomic */
	res->gpu_address = sscreen->ws->buffer_get_virtual_address(res->buf);

	if (res->flags & RADEON_FLAG_32BIT) {
		uint64_t start = res->gpu_address;
		uint64_t last = start + res->bo_size - 1;
		(void)start;
		(void)last;

		assert((start >> 32) == sscreen->info.address32_hi);
		assert((last >> 32) == sscreen->info.address32_hi);
	}

	pb_reference(&old_buf, NULL);

	util_range_set_empty(&res->valid_buffer_range);
	res->TC_L2_dirty = false;

	/* Print debug information. */
	if (sscreen->debug_flags & DBG(VM) && res->b.b.target == PIPE_BUFFER) {
		fprintf(stderr, "VM start=0x%"PRIX64"  end=0x%"PRIX64" | Buffer %"PRIu64" bytes\n",
			res->gpu_address, res->gpu_address + res->buf->size,
			res->buf->size);
	}

	if (res->b.b.flags & SI_RESOURCE_FLAG_CLEAR)
		si_screen_clear_buffer(sscreen, &res->b.b, 0, res->bo_size, 0);

	return true;
}

static void si_buffer_destroy(struct pipe_screen *screen,
			      struct pipe_resource *buf)
{
	struct si_resource *buffer = si_resource(buf);

	threaded_resource_deinit(buf);
	util_range_destroy(&buffer->valid_buffer_range);
	pb_reference(&buffer->buf, NULL);
	FREE(buffer);
}

/* Reallocate the buffer a update all resource bindings where the buffer is
 * bound.
 *
 * This is used to avoid CPU-GPU synchronizations, because it makes the buffer
 * idle by discarding its contents.
 */
static bool
si_invalidate_buffer(struct si_context *sctx,
		     struct si_resource *buf)
{
	/* Shared buffers can't be reallocated. */
	if (buf->b.is_shared)
		return false;

	/* Sparse buffers can't be reallocated. */
	if (buf->flags & RADEON_FLAG_SPARSE)
		return false;

	/* In AMD_pinned_memory, the user pointer association only gets
	 * broken when the buffer is explicitly re-allocated.
	 */
	if (buf->b.is_user_ptr)
		return false;

	/* Check if mapping this buffer would cause waiting for the GPU. */
	if (si_rings_is_buffer_referenced(sctx, buf->buf, RADEON_USAGE_READWRITE) ||
	    !sctx->ws->buffer_wait(buf->buf, 0, RADEON_USAGE_READWRITE)) {
		/* Reallocate the buffer in the same pipe_resource. */
		si_alloc_resource(sctx->screen, buf);
		si_rebind_buffer(sctx, &buf->b.b);
	} else {
		util_range_set_empty(&buf->valid_buffer_range);
	}

	return true;
}

/* Replace the storage of dst with src. */
void si_replace_buffer_storage(struct pipe_context *ctx,
				 struct pipe_resource *dst,
				 struct pipe_resource *src)
{
	struct si_context *sctx = (struct si_context*)ctx;
	struct si_resource *sdst = si_resource(dst);
	struct si_resource *ssrc = si_resource(src);

	pb_reference(&sdst->buf, ssrc->buf);
	sdst->gpu_address = ssrc->gpu_address;
	sdst->b.b.bind = ssrc->b.b.bind;
	sdst->b.max_forced_staging_uploads = ssrc->b.max_forced_staging_uploads;
	sdst->max_forced_staging_uploads = ssrc->max_forced_staging_uploads;
	sdst->flags = ssrc->flags;

	assert(sdst->vram_usage == ssrc->vram_usage);
	assert(sdst->gart_usage == ssrc->gart_usage);
	assert(sdst->bo_size == ssrc->bo_size);
	assert(sdst->bo_alignment == ssrc->bo_alignment);
	assert(sdst->domains == ssrc->domains);

	si_rebind_buffer(sctx, dst);
}

static void si_invalidate_resource(struct pipe_context *ctx,
				   struct pipe_resource *resource)
{
	struct si_context *sctx = (struct si_context*)ctx;
	struct si_resource *buf = si_resource(resource);

	/* We currently only do anyting here for buffers */
	if (resource->target == PIPE_BUFFER)
		(void)si_invalidate_buffer(sctx, buf);
}

static void *si_buffer_get_transfer(struct pipe_context *ctx,
				    struct pipe_resource *resource,
				    unsigned usage,
				    const struct pipe_box *box,
				    struct pipe_transfer **ptransfer,
				    void *data, struct si_resource *staging,
				    unsigned offset)
{
	struct si_context *sctx = (struct si_context*)ctx;
	struct si_transfer *transfer;

	if (usage & TC_TRANSFER_MAP_THREADED_UNSYNC)
		transfer = slab_alloc(&sctx->pool_transfers_unsync);
	else
		transfer = slab_alloc(&sctx->pool_transfers);

	transfer->b.b.resource = NULL;
	pipe_resource_reference(&transfer->b.b.resource, resource);
	transfer->b.b.level = 0;
	transfer->b.b.usage = usage;
	transfer->b.b.box = *box;
	transfer->b.b.stride = 0;
	transfer->b.b.layer_stride = 0;
	transfer->b.staging = NULL;
	transfer->offset = offset;
	transfer->staging = staging;
	*ptransfer = &transfer->b.b;
	return data;
}

static void *si_buffer_transfer_map(struct pipe_context *ctx,
				    struct pipe_resource *resource,
				    unsigned level,
				    unsigned usage,
				    const struct pipe_box *box,
				    struct pipe_transfer **ptransfer)
{
	struct si_context *sctx = (struct si_context*)ctx;
	struct si_resource *buf = si_resource(resource);
	uint8_t *data;

	assert(box->x + box->width <= resource->width0);

	/* From GL_AMD_pinned_memory issues:
	 *
	 *     4) Is glMapBuffer on a shared buffer guaranteed to return the
	 *        same system address which was specified at creation time?
	 *
	 *        RESOLVED: NO. The GL implementation might return a different
	 *        virtual mapping of that memory, although the same physical
	 *        page will be used.
	 *
	 * So don't ever use staging buffers.
	 */
	if (buf->b.is_user_ptr)
		usage |= PIPE_TRANSFER_PERSISTENT;

	/* See if the buffer range being mapped has never been initialized,
	 * in which case it can be mapped unsynchronized. */
	if (!(usage & (PIPE_TRANSFER_UNSYNCHRONIZED |
		       TC_TRANSFER_MAP_NO_INFER_UNSYNCHRONIZED)) &&
	    usage & PIPE_TRANSFER_WRITE &&
	    !buf->b.is_shared &&
	    !util_ranges_intersect(&buf->valid_buffer_range, box->x, box->x + box->width)) {
		usage |= PIPE_TRANSFER_UNSYNCHRONIZED;
	}

	/* If discarding the entire range, discard the whole resource instead. */
	if (usage & PIPE_TRANSFER_DISCARD_RANGE &&
	    box->x == 0 && box->width == resource->width0) {
		usage |= PIPE_TRANSFER_DISCARD_WHOLE_RESOURCE;
	}

	/* If a buffer in VRAM is too large and the range is discarded, don't
	 * map it directly. This makes sure that the buffer stays in VRAM.
	 */
	bool force_discard_range = false;
	if (usage & (PIPE_TRANSFER_DISCARD_WHOLE_RESOURCE |
		     PIPE_TRANSFER_DISCARD_RANGE) &&
	    !(usage & PIPE_TRANSFER_PERSISTENT) &&
	    /* Try not to decrement the counter if it's not positive. Still racy,
	     * but it makes it harder to wrap the counter from INT_MIN to INT_MAX. */
	    buf->max_forced_staging_uploads > 0 &&
	    p_atomic_dec_return(&buf->max_forced_staging_uploads) >= 0) {
		usage &= ~(PIPE_TRANSFER_DISCARD_WHOLE_RESOURCE |
			   PIPE_TRANSFER_UNSYNCHRONIZED);
		usage |= PIPE_TRANSFER_DISCARD_RANGE;
		force_discard_range = true;
	}

	if (usage & PIPE_TRANSFER_DISCARD_WHOLE_RESOURCE &&
	    !(usage & (PIPE_TRANSFER_UNSYNCHRONIZED |
		       TC_TRANSFER_MAP_NO_INVALIDATE))) {
		assert(usage & PIPE_TRANSFER_WRITE);

		if (si_invalidate_buffer(sctx, buf)) {
			/* At this point, the buffer is always idle. */
			usage |= PIPE_TRANSFER_UNSYNCHRONIZED;
		} else {
			/* Fall back to a temporary buffer. */
			usage |= PIPE_TRANSFER_DISCARD_RANGE;
		}
	}

	if (usage & PIPE_TRANSFER_FLUSH_EXPLICIT &&
	    buf->b.b.flags & SI_RESOURCE_FLAG_UPLOAD_FLUSH_EXPLICIT_VIA_SDMA) {
		usage &= ~(PIPE_TRANSFER_UNSYNCHRONIZED |
			   PIPE_TRANSFER_PERSISTENT);
		usage |= PIPE_TRANSFER_DISCARD_RANGE;
		force_discard_range = true;
	}

	if (usage & PIPE_TRANSFER_DISCARD_RANGE &&
	    ((!(usage & (PIPE_TRANSFER_UNSYNCHRONIZED |
			 PIPE_TRANSFER_PERSISTENT))) ||
	     (buf->flags & RADEON_FLAG_SPARSE))) {
		assert(usage & PIPE_TRANSFER_WRITE);

		/* Check if mapping this buffer would cause waiting for the GPU.
		 */
		if (buf->flags & RADEON_FLAG_SPARSE ||
		    force_discard_range ||
		    si_rings_is_buffer_referenced(sctx, buf->buf, RADEON_USAGE_READWRITE) ||
		    !sctx->ws->buffer_wait(buf->buf, 0, RADEON_USAGE_READWRITE)) {
			/* Do a wait-free write-only transfer using a temporary buffer. */
			struct u_upload_mgr *uploader;
			struct si_resource *staging = NULL;
			unsigned offset;

			/* If we are not called from the driver thread, we have
			 * to use the uploader from u_threaded_context, which is
			 * local to the calling thread.
			 */
			if (usage & TC_TRANSFER_MAP_THREADED_UNSYNC)
				uploader = sctx->tc->base.stream_uploader;
			else
				uploader = sctx->b.stream_uploader;

			u_upload_alloc(uploader, 0,
                                       box->width + (box->x % SI_MAP_BUFFER_ALIGNMENT),
				       sctx->screen->info.tcc_cache_line_size,
				       &offset, (struct pipe_resource**)&staging,
                                       (void**)&data);

			if (staging) {
				data += box->x % SI_MAP_BUFFER_ALIGNMENT;
				return si_buffer_get_transfer(ctx, resource, usage, box,
								ptransfer, data, staging, offset);
			} else if (buf->flags & RADEON_FLAG_SPARSE) {
				return NULL;
			}
		} else {
			/* At this point, the buffer is always idle (we checked it above). */
			usage |= PIPE_TRANSFER_UNSYNCHRONIZED;
		}
	}
	/* Use a staging buffer in cached GTT for reads. */
	else if (((usage & PIPE_TRANSFER_READ) &&
		  !(usage & PIPE_TRANSFER_PERSISTENT) &&
		  (buf->domains & RADEON_DOMAIN_VRAM ||
		   buf->flags & RADEON_FLAG_GTT_WC)) ||
		 (buf->flags & RADEON_FLAG_SPARSE)) {
		struct si_resource *staging;

		assert(!(usage & TC_TRANSFER_MAP_THREADED_UNSYNC));
		staging = si_resource(pipe_buffer_create(
				ctx->screen, 0, PIPE_USAGE_STAGING,
				box->width + (box->x % SI_MAP_BUFFER_ALIGNMENT)));
		if (staging) {
			/* Copy the VRAM buffer to the staging buffer. */
			sctx->dma_copy(ctx, &staging->b.b, 0,
				       box->x % SI_MAP_BUFFER_ALIGNMENT,
				       0, 0, resource, 0, box);

			data = si_buffer_map_sync_with_rings(sctx, staging,
							     usage & ~PIPE_TRANSFER_UNSYNCHRONIZED);
			if (!data) {
				si_resource_reference(&staging, NULL);
				return NULL;
			}
			data += box->x % SI_MAP_BUFFER_ALIGNMENT;

			return si_buffer_get_transfer(ctx, resource, usage, box,
							ptransfer, data, staging, 0);
		} else if (buf->flags & RADEON_FLAG_SPARSE) {
			return NULL;
		}
	}

	data = si_buffer_map_sync_with_rings(sctx, buf, usage);
	if (!data) {
		return NULL;
	}
	data += box->x;

	return si_buffer_get_transfer(ctx, resource, usage, box,
					ptransfer, data, NULL, 0);
}

static void si_buffer_do_flush_region(struct pipe_context *ctx,
				      struct pipe_transfer *transfer,
				      const struct pipe_box *box)
{
	struct si_context *sctx = (struct si_context*)ctx;
	struct si_transfer *stransfer = (struct si_transfer*)transfer;
	struct si_resource *buf = si_resource(transfer->resource);

	if (stransfer->staging) {
		unsigned src_offset = stransfer->offset +
				      transfer->box.x % SI_MAP_BUFFER_ALIGNMENT +
				      (box->x - transfer->box.x);

		if (buf->b.b.flags & SI_RESOURCE_FLAG_UPLOAD_FLUSH_EXPLICIT_VIA_SDMA) {
			/* This should be true for all uploaders. */
			assert(transfer->box.x == 0);

			/* Find a previous upload and extend its range. The last
			 * upload is likely to be at the end of the list.
			 */
			for (int i = sctx->num_sdma_uploads - 1; i >= 0; i--) {
				struct si_sdma_upload *up = &sctx->sdma_uploads[i];

				if (up->dst != buf)
					continue;

				assert(up->src == stransfer->staging);
				assert(box->x > up->dst_offset);
				up->size = box->x + box->width - up->dst_offset;
				return;
			}

			/* Enlarge the array if it's full. */
			if (sctx->num_sdma_uploads == sctx->max_sdma_uploads) {
				unsigned size;

				sctx->max_sdma_uploads += 4;
				size = sctx->max_sdma_uploads * sizeof(sctx->sdma_uploads[0]);
				sctx->sdma_uploads = realloc(sctx->sdma_uploads, size);
			}

			/* Add a new upload. */
			struct si_sdma_upload *up =
				&sctx->sdma_uploads[sctx->num_sdma_uploads++];
			up->dst = up->src = NULL;
			si_resource_reference(&up->dst, buf);
			si_resource_reference(&up->src, stransfer->staging);
			up->dst_offset = box->x;
			up->src_offset = src_offset;
			up->size = box->width;
			return;
		}

		/* Copy the staging buffer into the original one. */
		si_copy_buffer(sctx, transfer->resource, &stransfer->staging->b.b,
			       box->x, src_offset, box->width);
	}

	util_range_add(&buf->valid_buffer_range, box->x,
		       box->x + box->width);
}

static void si_buffer_flush_region(struct pipe_context *ctx,
				   struct pipe_transfer *transfer,
				   const struct pipe_box *rel_box)
{
	unsigned required_usage = PIPE_TRANSFER_WRITE |
				  PIPE_TRANSFER_FLUSH_EXPLICIT;

	if ((transfer->usage & required_usage) == required_usage) {
		struct pipe_box box;

		u_box_1d(transfer->box.x + rel_box->x, rel_box->width, &box);
		si_buffer_do_flush_region(ctx, transfer, &box);
	}
}

static void si_buffer_transfer_unmap(struct pipe_context *ctx,
				     struct pipe_transfer *transfer)
{
	struct si_context *sctx = (struct si_context*)ctx;
	struct si_transfer *stransfer = (struct si_transfer*)transfer;

	if (transfer->usage & PIPE_TRANSFER_WRITE &&
	    !(transfer->usage & PIPE_TRANSFER_FLUSH_EXPLICIT))
		si_buffer_do_flush_region(ctx, transfer, &transfer->box);

	si_resource_reference(&stransfer->staging, NULL);
	assert(stransfer->b.staging == NULL); /* for threaded context only */
	pipe_resource_reference(&transfer->resource, NULL);

	/* Don't use pool_transfers_unsync. We are always in the driver
	 * thread. */
	slab_free(&sctx->pool_transfers, transfer);
}

static void si_buffer_subdata(struct pipe_context *ctx,
			      struct pipe_resource *buffer,
			      unsigned usage, unsigned offset,
			      unsigned size, const void *data)
{
	struct pipe_transfer *transfer = NULL;
	struct pipe_box box;
	uint8_t *map = NULL;

	u_box_1d(offset, size, &box);
	map = si_buffer_transfer_map(ctx, buffer, 0,
				       PIPE_TRANSFER_WRITE |
				       PIPE_TRANSFER_DISCARD_RANGE |
				       usage,
				       &box, &transfer);
	if (!map)
		return;

	memcpy(map, data, size);
	si_buffer_transfer_unmap(ctx, transfer);
}

static const struct u_resource_vtbl si_buffer_vtbl =
{
	NULL,				/* get_handle */
	si_buffer_destroy,		/* resource_destroy */
	si_buffer_transfer_map,	/* transfer_map */
	si_buffer_flush_region,	/* transfer_flush_region */
	si_buffer_transfer_unmap,	/* transfer_unmap */
};

static struct si_resource *
si_alloc_buffer_struct(struct pipe_screen *screen,
		       const struct pipe_resource *templ)
{
	struct si_resource *buf;

	buf = MALLOC_STRUCT(si_resource);

	buf->b.b = *templ;
	buf->b.b.next = NULL;
	pipe_reference_init(&buf->b.b.reference, 1);
	buf->b.b.screen = screen;

	buf->b.vtbl = &si_buffer_vtbl;
	threaded_resource_init(&buf->b.b);

	buf->buf = NULL;
	buf->bind_history = 0;
	buf->TC_L2_dirty = false;
	util_range_init(&buf->valid_buffer_range);
	return buf;
}

static struct pipe_resource *si_buffer_create(struct pipe_screen *screen,
					      const struct pipe_resource *templ,
					      unsigned alignment)
{
	struct si_screen *sscreen = (struct si_screen*)screen;
	struct si_resource *buf = si_alloc_buffer_struct(screen, templ);

	if (templ->flags & PIPE_RESOURCE_FLAG_SPARSE)
		buf->b.b.flags |= SI_RESOURCE_FLAG_UNMAPPABLE;

	si_init_resource_fields(sscreen, buf, templ->width0, alignment);

	if (templ->flags & PIPE_RESOURCE_FLAG_SPARSE)
		buf->flags |= RADEON_FLAG_SPARSE;

	if (!si_alloc_resource(sscreen, buf)) {
		FREE(buf);
		return NULL;
	}
	return &buf->b.b;
}

struct pipe_resource *pipe_aligned_buffer_create(struct pipe_screen *screen,
						 unsigned flags, unsigned usage,
						 unsigned size, unsigned alignment)
{
	struct pipe_resource buffer;

	memset(&buffer, 0, sizeof buffer);
	buffer.target = PIPE_BUFFER;
	buffer.format = PIPE_FORMAT_R8_UNORM;
	buffer.bind = 0;
	buffer.usage = usage;
	buffer.flags = flags;
	buffer.width0 = size;
	buffer.height0 = 1;
	buffer.depth0 = 1;
	buffer.array_size = 1;
	return si_buffer_create(screen, &buffer, alignment);
}

struct si_resource *si_aligned_buffer_create(struct pipe_screen *screen,
					       unsigned flags, unsigned usage,
					       unsigned size, unsigned alignment)
{
	return si_resource(pipe_aligned_buffer_create(screen, flags, usage,
							size, alignment));
}

static struct pipe_resource *
si_buffer_from_user_memory(struct pipe_screen *screen,
			   const struct pipe_resource *templ,
			   void *user_memory)
{
	struct si_screen *sscreen = (struct si_screen*)screen;
	struct radeon_winsys *ws = sscreen->ws;
	struct si_resource *buf = si_alloc_buffer_struct(screen, templ);

	buf->domains = RADEON_DOMAIN_GTT;
	buf->flags = 0;
	buf->b.is_user_ptr = true;
	util_range_add(&buf->valid_buffer_range, 0, templ->width0);
	util_range_add(&buf->b.valid_buffer_range, 0, templ->width0);

	/* Convert a user pointer to a buffer. */
	buf->buf = ws->buffer_from_ptr(ws, user_memory, templ->width0);
	if (!buf->buf) {
		FREE(buf);
		return NULL;
	}

	buf->gpu_address = ws->buffer_get_virtual_address(buf->buf);
	buf->vram_usage = 0;
	buf->gart_usage = templ->width0;

	return &buf->b.b;
}

static struct pipe_resource *si_resource_create(struct pipe_screen *screen,
						const struct pipe_resource *templ)
{
	if (templ->target == PIPE_BUFFER) {
		return si_buffer_create(screen, templ, 256);
	} else {
		return si_texture_create(screen, templ);
	}
}

static bool si_resource_commit(struct pipe_context *pctx,
			       struct pipe_resource *resource,
			       unsigned level, struct pipe_box *box,
			       bool commit)
{
	struct si_context *ctx = (struct si_context *)pctx;
	struct si_resource *res = si_resource(resource);

	/*
	 * Since buffer commitment changes cannot be pipelined, we need to
	 * (a) flush any pending commands that refer to the buffer we're about
	 *     to change, and
	 * (b) wait for threaded submit to finish, including those that were
	 *     triggered by some other, earlier operation.
	 */
	if (radeon_emitted(ctx->gfx_cs, ctx->initial_gfx_cs_size) &&
	    ctx->ws->cs_is_buffer_referenced(ctx->gfx_cs,
					       res->buf, RADEON_USAGE_READWRITE)) {
		si_flush_gfx_cs(ctx, RADEON_FLUSH_ASYNC_START_NEXT_GFX_IB_NOW, NULL);
	}
	if (radeon_emitted(ctx->dma_cs, 0) &&
	    ctx->ws->cs_is_buffer_referenced(ctx->dma_cs,
					       res->buf, RADEON_USAGE_READWRITE)) {
		si_flush_dma_cs(ctx, PIPE_FLUSH_ASYNC, NULL);
	}

	ctx->ws->cs_sync_flush(ctx->dma_cs);
	ctx->ws->cs_sync_flush(ctx->gfx_cs);

	assert(resource->target == PIPE_BUFFER);

	return ctx->ws->buffer_commit(res->buf, box->x, box->width, commit);
}

void si_init_screen_buffer_functions(struct si_screen *sscreen)
{
	sscreen->b.resource_create = si_resource_create;
	sscreen->b.resource_destroy = u_resource_destroy_vtbl;
	sscreen->b.resource_from_user_memory = si_buffer_from_user_memory;
}

void si_init_buffer_functions(struct si_context *sctx)
{
	sctx->b.invalidate_resource = si_invalidate_resource;
	sctx->b.transfer_map = u_transfer_map_vtbl;
	sctx->b.transfer_flush_region = u_transfer_flush_region_vtbl;
	sctx->b.transfer_unmap = u_transfer_unmap_vtbl;
	sctx->b.texture_subdata = u_default_texture_subdata;
	sctx->b.buffer_subdata = si_buffer_subdata;
	sctx->b.resource_commit = si_resource_commit;
}